Tube diffusers are conventionally used to support aerobic biological processes in wastewater treatment plants. A tube diffuser typically comprises a cylindrical flexible diffuser membrane that covers a rigid cylindrical support tube. Supplying pressurized air to the tube diffuser while the tube diffuser is immersed in wastewater has the effect of expanding the flexible diffuser membrane away from the support tube and causing the air to escape into the wastewater through a multiplicity of perforations in the flexible diffuser membrane. The effect is a plume of small bubbles that act both to oxygenate the biological processes occurring in the wastewater treatment tank and to provide a mixing function. Wastewater treatment in such a manner is described in, as just one example, F. L. Burton, Wastewater Engineering (McGraw-Hill College, 2002), which is hereby incorporated by reference herein.
Despite their popularity, the installation and servicing of tube diffusers remain relatively labor intensive tasks, and generally require the use of skilled labor. If not installed correctly, a tube diffuser may leak causing a non-uniform distribution of bubbles. Even worse, a leak may allow wastewater to enter (i.e., flood) the submerged air piping of the wastewater treatment system. If either one of these issues is present, a wastewater treatment tank may need to be drained to re-access and repair the defects. Such repairs may be time-consuming, expensive, and will clearly take the wastewater treatment tank offline.
There is as a result a need for alternative diffuser assemblies that address some of the above-identified deficiencies.